New rules for energy efficient motors are set to apply throughout the EU from July and with the United Nations’ COP26 climate conference scheduled to take place in November, now is a good moment to think again about what it means for the process industries, says Michelle Knott.
The European Commission has already indicated that EU regulations around energy efficiency are going to get tighter in future and it is easy to see why. The estimated eight billion electric motors in use today across Europe consume approximately 50% of the electric power generated in the EU. They therefore play a decisive role when it comes to reducing energy consumption.
While the European Commission is ahead of many other jurisdictions when it comes to regulation, legislators around the world look likely to take a similar firm line as the pressure builds to meet climate targets and drive down CO2 emissions.
The Commission’s latest move is to introduce a new regulation on electric motors and variable speed drives, (EU) 2019/1781, which replaces the existing 640/2009/EC. The new rules set out Minimum Efficiency Performance Standards and include several other notable changes to the existing regime.
First, several categories of induction motor will be regulated for energy efficiency for the first time from July. These include smaller motors between 120W and 750W, larger motors between 375kW and 1,000kW, 60Hz motors and 8-poles motors. Single-phase motors will also be included from July 2023. In addition, three-phase motors with a rated output between 0.75kW and equal to or below 1,000kW must meet IE3 levels of perfor-mance by July 2021, while motors between 75kW and 200kW must meet IE4 levels from July 2023.
The regulation will also specify the efficiency of variable speed drives and both product groups will be subject to information requirements such as efficiency at different load points, in terms of speed and torque.
This will help engineers to optimise the efficiency of entire drive systems, rather than focusing on individual items of equipment.
More efficient motors under the old regulation delivered 57 terawatt-hours of annual energy savings in the EU by 2020. Taking into account the overall effect of the revised regulation, the Commission expects these annual savings will increase to 110 terawatt-hours by 2030, which is equivalent to the electricity consumption of the Netherlands. This means that 40 million tonnes of CO2 emissions will be avoided each year and that the annual energy bill for the EU’s households and industry will be reduced by something in the region of €20 billion by 2030.
Industrial energy efficiency, more than any other challenge, has the single greatest capacity for combating the climate emergency. It is essentially the world’s invisible climate solution
Morten Wierod, president, ABB Motion
A strong regulatory regime has an important global role to play in tackling emissions, acknowledged Morten Wierod, president of ABB Motion, at the launch of a white paper on high-efficiency motors earlier this year: “Regulatory policies are among the main drivers of industrial investment in energy efficiency around the globe. While the European Union will be implementing its Ecodesign Regulation (EU 2019/1781) this year, which sets out stringent new requirements for an expanding range of energy efficient motors, many countries have yet to take action. Industrial energy efficiency, more than any other challenge, has the single greatest capacity for combating the climate emergency. It is essentially the world’s invisible climate solution,” he said.
“The importance of transitioning industries and infrastructure to these highly energy efficient drives and motors to play their part in a more sustainable society cannot be overstated. With 45% of the world’s electricity used to power electric motors in buildings and industrial applications, investment in upgrading yields outsized rewards in terms of efficiency.”
For example, ABB claims that its own high efficiency motors and drives alone enabled 198 terawatt-hours of electricity savings in 2020, which is more than half of the UK’s annual consumption. At this rate, it estimates that its motors and drives will enable customers globally to save an additional 78 terawatt- hours of electricity per year by 2023, which is almost as much as the annual consumption of Belgium, Finland or the Philippines.
From a purely business perspective, the good thing about tightening standards around energy efficiency is that it should also save money throughout the life of a motor, even if it means investing more upfront. Users are missing a trick if they do not reduce the cost of running electric motor systems.
Tony Young, director of CP Automation [pictured], which supplies drives, controls and resistors, says: “Companies that do invest in energy reduction rarely get much further than fitting VFDs or haggling on price per kilowatt hour. There are a host of additional measures that can be addressed with little capital expenditure.”
The first step is to make sure that motors and drives are specified correctly. Young puts it very simply: “You wouldn’t buy a minibus for a family of four. Design engineers love to over specify ‘for tomorrow’ but for plant and maintenance professionals this just means bigger energy bills,” he explains. “If you plan to add a VFD now or later as a retrofit product, ensure that the motor is VFD rated to start with. Otherwise, any retrofit project will involve replacing the motor.
“Over specification also raises maintenance bills. I’ve seen countless motors, which are doing an easy job like water pumping, specified at a much higher capacity than is required. Sometimes this is to the point that the motor costs £2,000 but the same job could be done by a motor costing £1,000.”
In addition, while a simple drive system is generally better in terms of ongoing maintenance costs, Young also acknowledges that the addition of relatively simple add-ons can have a big impact on energy efficiency in some applications, without always opting for the ‘gold standard’ of installing an all-singing, all-dancing VFD.
For instance, VFDs come into their own in applications with varying loads, where they can adjust the motor output to track demand. However, many applications have a steady load once they are up and running. In this case, the extra power drawn each time they accelerate from a standing start might be the bigger issue.
Over specification also raises maintenance bills. I’ve seen countless motors, which are doing an easy job like water pumping, specified at a much higher capacity than is required
Tony Young, director, CP Automation
“Soft starts are increasingly common on pump applications and they dramatically reduce the energy used when starting a motor. They are also common on conveyors, where the smooth start prevents objects from falling. As an alternative to a motor starter resistor or a VFD they can be more profitable, but only if the application is assessed correctly in the first instance and the device is sized appropriately,” says Young.
Meanwhile, running equipment when it is not needed is another obvious target for potential savings and fitting timers can help minimise unnecessary activity. Young adds: “Timing devices can be a hugely underused in the chemical industry and are a very cost-effective way of saving energy on non-continuous use applications. Often pumps and ventilators run constantly, even if there are times of day when there is no demand.
“You’re not just saving energy from not running a motor unnecessarily, but from elongating the life of your systems. For example, the hydraulic pumping efficiency of your cooling systems.”
Energy represents approximately 97% of the operating costs of an electric motor, so the pressure from regulators may mean paying more for higher-quality drives and motors up front but users will reap the benefit over the lifetime of the equipment.